Prior art devices of the type described above are disclosed in French patent application No. 2,502,086 and in U.S. Pat. No. 2,924,839. In the French patent application means are provided for retaining backing strips of a wiping element and the assembled wiping element/backing strips are locked with respect to one of the claws of the superstructure of the wiper blade by means of two lips cut in each backing strip respectively on each side of the claw and bent outwardly with respect to the longitudinal axis of the wiping element. A similar system is disclosed in the U.S. patent, the only difference being that the two lips are not bent outwardly, but rather upwardly and downwardly with respect to the longitudinal axis of the wiping element.
Another prior art structure for securing a wiping element to wiper blade superstructure is shown in U.S. Pat. No. 3,386,123. A backing strip is stamped from a flat strip of flexible material and has inwardly projecting protuberances to compress a portion of the wiping element to which it connects. The principal problem with the device in U.S. Pat. No. 3,386,123 is that the backing strips, being formed by a stamping operation, are relatively difficult to manufacture and, therefore, the manufacturing process is costly.